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arXiv · 0804.2964

Structural properties and liquid spinodal of water confined in a hydrophobic environment

P. Gallo·M. Rovere
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Abstract

We present the results of a computer simulation study of thermodynamical properties of TIP4P water confined in a hydrophobic disordered matrix of soft spheres upon supercooling. The hydrogen bond network of water appears preserved in this hydrophobic confinement. Nonetheless a reduction in the average number of hydrogen bonds due to the geometrical constraints is observed. The liquid branch of the spinodal line is calculated from 350 K down to 210 K. The same thermodynamic scenario of the bulk is found: the spinodal curve is monotonically decreasing. The line of maximum density bends avoiding a crossing of the spinodal. There is however a shift both of the line of maximum density and of the spinodal toward higher pressures and lower temperatures with respect to bulk.

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P. Gallo, M. Rovere. 2008-04-18. Structural properties and liquid spinodal of water confined in a hydrophobic environment. https://doi.org/10.1103/physreve.76.061202

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